Simultaneous determination of Cr(III) and Cr(VI) using differential pulse polarography and application to Gerede River

Olcay ŞENDİL; Nabeel MOHAMMED; Güler SOMER

Makale detayları

Simultaneous determination of Cr(III) and Cr(VI) using differential pulse polarography and application to Gerede River

Yazarlar:

Olcay ŞENDİL | Nabeel MOHAMMED | Güler SOMER

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Chemistry 2012 Vol.36 Issue 2, pp.335-346

Belge Tipi:

Makale

Yayın Tarihi:

1/2012

Belge Dili:

Türkçe

Document ID (Org No.):

2000727671

Sıklık:

İki Aylık

eISSN:

1303-6130

pISSN:

1300-0527

Özet:

 

Determination of Cr(III) in the presence of Cr(VI) from one  polarogram is not easy.  No such procedure was found in the  literature.  In polarographic studies Cr(III) had a peak only in  acidic medium, while Cr(VI) had either 1 or 2 peaks in both acidic and  basic solutions.  In solutions that contain these 2 ions, the peak  obtained in acidic medium for Cr(III) will be the sum of both ions.  Thus, Cr(III) cannot be determined directly from one polarogram.  In this work, a new and simple polarographic method is established for  the determination of Cr(III) and Cr(VI) by using only one polarogram.  The most suitable electrolyte for this purpose was 0.1 M KNO3/HNO3  (pH 2-3).  The detection limits were 3 \times 10-7 M for Cr(III)  and 1 \times 10-6 M for Cr(VI) in this medium.  No interference was  observed from most common ions.  For validation, a sample containing  both Cr(VI) and Cr(III) was analyzed also using 2 polarograms and good  agreement was obtained.  The proposed newly established direct method  is applied to a real sample.  For this purpose Gerede River in Turkey,  which is surrounded by many leather factories, was analyzed for its  chromium content, and agreement with ICP -- OES was very good.

 

Determination of Cr(III) in the presence of Cr(VI) from one  polarogram is not easy.  No such procedure was found in the  literature.  In polarographic studies Cr(III) had a peak only in  acidic medium, while Cr(VI) had either 1 or 2 peaks in both acidic and  basic solutions.  In solutions that contain these 2 ions, the peak  obtained in acidic medium for Cr(III) will be the sum of both ions.  Thus, Cr(III) cannot be determined directly from one polarogram.  In this work, a new and simple polarographic method is established for  the determination of Cr(III) and Cr(VI) by using only one polarogram.  The most suitable electrolyte for this purpose was 0.1 M KNO3/HNO3  (pH 2-3).  The detection limits were 3 \times 10-7 M for Cr(III)  and 1 \times 10-6 M for Cr(VI) in this medium.  No interference was  observed from most common ions.  For validation, a sample containing  both Cr(VI) and Cr(III) was analyzed also using 2 polarograms and good  agreement was obtained.  The proposed newly established direct method  is applied to a real sample.  For this purpose Gerede River in Turkey,  which is surrounded by many leather factories, was analyzed for its  chromium content, and agreement with ICP -- OES was very good.

Makale detayları

Simultaneous determination of Cr(III) and Cr(VI) using differential pulse polarography and application to Gerede River

Yazarlar: Olcay ŞENDİL | Nabeel MOHAMMED | Güler SOMER

Yayıncı: TUBITAK

Dergi: Turkish Journal of Chemistry 2012 Vol.36 Issue 2, pp.335-346

Belge Tipi: Makale

Yayın Tarihi: 1/2012

Belge Dili: Türkçe

Document ID (Org No.): 2000727671

Sıklık: İki Aylık

eISSN: 1303-6130

pISSN: 1300-0527

Sayı

Yazarlar:

Olcay ŞENDİL | Nabeel MOHAMMED | Güler SOMER

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Chemistry 2012 Vol.36 Issue 2, pp.335-346

Belge Tipi:

Makale

Yayın Tarihi:

1/2012

Belge Dili:

Türkçe

Document ID (Org No.):

2000727671

Sıklık:

İki Aylık

eISSN:

1303-6130

pISSN:

1300-0527